The field of the present invention is cargo aircraft for transporting modular containers.
The basic unit for transporting goods has been the truck. Being the basic unit, the truck has defined limitations on intermodal containers that can typically be transported by ships, trains and trucks. Much of commerce today for which intermodal containers are most convenient are high volume, low weight products, computers being one example. Thus, volume instead of weight creates the limiting factor in the design of intermodal containers. As such, containers have grown to the maximum volume capacity of the basic unit, the truck. As such, intermodal containers are limited by the dimensions allowed by highway infrastructures.
The aforementioned intermodal containers have greatly facilitated and lowered the cost of cargo transportation. However, air cargo has generally been excluded from participation in intermodal cargo systems. Aircraft of a size capable of carrying substantial cargo have typically been designed first as passenger aircraft. Cylindrical fuselages and lack of large access ports thereto in such passenger aircraft limit the use of such aircraft for truly intermodal cargo systems. Rather, the aircraft must become the basic unit with odd shaped and smaller sized containers. As a result, even with containerized cargo, a truck must be loaded with multiple individual containers for efficient distribution of air cargo. Such aircraft are also designed to be efficient at high speeds which is costly. Military transports are also not particularly compatible with intermodal cargo systems as they are designed for oversized cargo such as rolling equipment, e.g., tanks and trucks, and palletized, irregularly shaped cargo. Most aircraft specifically designed for the military also are mission directed and overall efficiency for competitive cargo transportation is not a first priority.
The inability of aircraft to participate in intermodal container cargo systems has been disadvantageous to international commerce. Business principals such as just-in-time supply and changing business environments including rapid global internet communication have created a demand for much more rapid international shipping than can be provided by conventional ships. However, air cargo systems remain both expensive and inconvenient to intermodal shipping.